US will defend Baltic nations if necessary - Obama

Drawing on a broad sweep of history from the folly of Russian Tsars to Estonia under Soviet occupation, US President Barack Obama has taken aim at Moscow and sought to reassure Baltic nations that NATO and US troops would act to defend them.

Drawing on a broad sweep of history from the folly of Russian Tsars to Estonia under Soviet occupation, US President Barack Obama has taken aim at Moscow and sought to reassure Baltic nations that NATO and US troops would act to defend them.

Moscow's annexation of Crimea and support of a separatist uprising in Ukraine has provoked fears in some Eastern European, Baltic and Scandinavian states that their borders may also one day be the target for Russia's resurgent territorial ambitions.

Mr Obama made reference to Estonia's own past as a Soviet state, and vowed that its independence would be defended. "I say to the people of Estonia and the people of Baltics, today we are bound by our treaty alliance," he told an audience in the Estonian capital, Tallinn.

"So if in such a moment you ever ask again who will come to help, you will know the answer: the NATO alliance, including the Armed Forces of the United States of America."

His forceful words may not be enough to placate some nations, however.